The invention relates to a lithium microbattery formed by a stack of solid thin layers on a substrate. Starting from the substrate, the stack successively comprises a first electrode, a solid electrolyte and a second electrode/current collector assembly formed by at least one thin layer, a first surface and a second surface of the electrolyte being in contact respectively with a main surface of the first electrode and a main surface of the second electrode/current collector assembly. The main surfaces are facing one another and the dimensions of the main surface of the first electrode are smaller than the dimensions of the main surface of the assembly.
The invention also relates to a fabrication method of such a microbattery.